Magnetorheological polishing equipment and method based on sensor adjustment

Abstract

The invention relates to the technical field of optical machining, in particular to magneto-rheological polishing equipment and method based on sensor adjustment, and the equipment comprises a laser tracker, a control unit, a robot, a magneto-rheological machining module and a sensor module; the magneto-rheological machining module is arranged at the free end of the robot, and the robot drives the magneto-rheological machining module to machine the optical element to be machined. The sensor module is arranged on the magneto-rheological processing module; the laser tracker is matched with the target ball to measure space coordinates of working points of polishing wheels in the sensor module and the magneto-rheological machining module; according to the method, a laser tracker and a sensor module are matched to measure the pose of a robot in the machining process, the position of a magneto-rheological machining module and the real-time change of a removal function during machining, and a supply system, a nozzle and an actuator in the magneto-rheological machining module are regulated and controlled in real time; and real-time constant control of the removal function of the to-be-processed optical element is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical processing, and particularly relates to a magnetorheological polishing device and method based on sensor adjustment. Background Art

[0002] Magnetorheological Finishing (MRF) is an advanced optical manufacturing technology developed in recent years. It has many advantages such as a stable removal function, controllable edge effect, small damage layer on the lower surface, no replication effect, strong shape correction ability, and high processing accuracy. Therefore, the magnetorheological polishing technology has received extensive attention in high-precision optical processing. The existing magnetorheological polishing machining centers mainly integrate the magnetorheological polishing module on a numerically controlled machine tool. However, some deficiencies of the numerically controlled machine tool (such as low degrees of freedom, large floor area, high cost, etc.) limit the deviation of the aspherical surface and it is difficult to perform precise pose control along the surface normal.

[0003] In view of these deficiencies of the numerically controlled machine tool, researchers have introduced six-degree-of-freedom industrial robots into the field of optical processing in recent years. Six-degree-of-freedom industrial robots have the advantages of high degrees of freedom, small floor area, large processing range, low cost, etc., making up for the deficiencies of the numerically controlled machine tool. Therefore, when integrating the magnetorheological polishing module on an industrial robot, it is theoretically possible to achieve high-precision processing of large-aperture complex-curved optical elements. However, due to the influence of factors such as processing, assembly, load, trajectory planning, and reduction ratio, the execution accuracy of the free end of the robot is relatively low, and the polishing gap changes greatly during the processing. At the same time, the magnetorheological polishing technology is an optical processing technology with a high degree of certainty of the removal function, and has high requirements for the change of the polishing gap during the polishing process. Generally, the change of the polishing gap in a magnetorheological numerical control machining center is within dozens of micrometers (PV < 0.1 mm), while the trajectory accuracy of common commercial robots is generally in the sub-millimeter to millimeter range. This leads to a large change in the polishing gap during the processing, reducing the certainty of the removal function and affecting the final processing accuracy. Therefore, the motion accuracy of current commercial large six-degree-of-freedom industrial robots often fails to meet the requirements of the magnetorheological polishing technology for the change of the removal function during high-precision polishing.

[0004] Regarding the problem of low motion accuracy of robots, the current real-time control scheme based on constant-force grinding and polishing has become a research hotspot. Among them, the force-position control method has become a common robot constant-force regulation grinding and polishing control method. A common application method is to place a force sensor between the processing tool and the robot. First, gravity calibration is performed on the force sensor to ensure accurate measurement. The pose error is calculated by measuring the change in force, and then the robot pose error is compensated by means of the robot body or other motion compensation mechanisms to achieve constant-force control. The high-efficiency processing of large-diameter optical elements relies on the magnetorheological processing module of a large-size polishing wheel, and the weight of the magnetorheological processing module of a large-size polishing wheel is generally hundreds of kilograms. However, for a magnetorheological processing module weighing hundreds of kilograms, the force change caused by the robot pose error is only dozens of Newtons. When performing high-precision processing, the force needs to be constant at several Newtons or even a fraction of a Newton, which requires the absolute measurement accuracy of measuring devices such as force sensors to reach one ten-thousandth, and the force sensor also needs to be in a state of variable speed and variable pose motion. Force sensors that meet these requirements are often extremely expensive, greatly increasing the cost of the equipment. Summary of the Invention

[0005] In view of this, the present invention aims to provide a magnetorheological polishing device and method based on sensor adjustment, which uses a laser tracker and a sensor module to cooperate to measure the real-time changes in the pose of the robot, the position of the magnetorheological processing module, and the removal function during the processing, and performs real-time regulation on the supply system, nozzle, and actuator in the magnetorheological processing module, so as to achieve real-time constant control of the removal function of the optical element.

[0006] To achieve the above object, the technical solution of the present invention is realized as follows: A magnetorheological finishing device based on sensor adjustment, comprising a laser tracker, a control unit, an actuator group, a robot, a magnetorheological processing module and a sensor module; wherein, the actuator group is arranged at the free end of the robot, and the magnetorheological processing module is arranged at the output end of the actuator group, so that the robot and the actuator group drive the magnetorheological processing module to process the optical element; the sensor module is arranged on the magnetorheological processing module; the laser tracker cooperates with a target ball arranged on the magnetorheological processing module to measure the spatial coordinates of the working point of the sensor module and the polishing wheel in the magnetorheological processing module; the interior of the control unit includes: a coordinate relationship module, which is used to integrate and calculate the spatial coordinates collected by the laser tracker and the position information collected by the sensor module, and output the integrated position information; a conversion relationship module, which is used to fit the first position of the supply system in the magnetorheological processing module with the polishing gap of the polishing wheel to obtain a first conversion relationship, and fit the second position of the nozzle in the magnetorheological processing module with the polishing gap to obtain a second conversion relationship; a machining program module, which is used to obtain a machining program according to the removal function generated when the magnetorheological processing equipment processes the optical element, and import the machining program into the magnetorheological processing equipment; a real-time regulation module, which is used to adjust the actuator group according to the integrated position information, or adjust the supply system according to the integrated position information and the first conversion relationship, or adjust the nozzle according to the integrated position information and the second conversion relationship, so as to keep the removal function stable when processing the optical element.

[0007] Further, the magnetorheological processing module further includes a transmission belt, a polishing motor, a magnet and a magnetorheological mounting bracket; wherein, the magnetorheological mounting bracket is arranged at the output end of the actuator group, and the polishing wheel is arranged on the magnetorheological mounting bracket; the polishing motor is arranged on the magnetorheological mounting bracket and is connected to the bearing of the polishing wheel through the transmission belt, so that the polishing motor controls the rotation of the polishing wheel; the nozzle is mounted on the magnetorheological mounting bracket along the rotation direction of the polishing wheel through a nozzle mounting seat, and the nozzle mounting seat adjusts the mounting angle of the nozzle, thereby changing the position of the nozzle orifice of the nozzle; the supply system conveys magnetorheological fluid to the nozzle; the magnet is arranged on the magnetorheological mounting bracket and close to the working point of the polishing wheel, so that the magnetorheological fluid is affected by the magnetic field intensity of the magnet and changes the stiffness of the magnetorheological fluid; the sensor module is arranged on the magnetorheological mounting bracket.

[0008] Further, the supply system includes a liquid pump, a supply mounting bracket, a supply motor and a lead screw; wherein, the supply motor and the lead screw are arranged on the supply mounting bracket, so that the supply motor drives the lead screw to rotate; the liquid pump is arranged on the nut of the lead screw, so that the lead screw drives the liquid pump to move, thereby changing the first position; the liquid pump conveys magnetorheological fluid to the nozzle through a pipeline.

[0009] Further, the nozzle mounting seat includes a fixing frame, a nozzle adjustment motor, a push rod, and a nozzle support frame. Among them, the fixing frame is arranged on the magnetorheological mounting frame, and arc-shaped slide rails are arranged on the inner side wall of the fixing frame. The nozzle adjustment motor is arranged on the magnetorheological mounting frame. One end of the push rod passes through the fixing frame and is connected to the nozzle adjustment motor, so that the nozzle adjustment motor drives the push rod to push the slider on the arc-shaped slide rail. One end of the nozzle support frame is arranged on the slider, and the nozzle is connected to the other end of the nozzle support frame, so that the nozzle adjustment motor drives the push rod to push the slider, and then the nozzle support frame drives the nozzle to move, thereby completing the adjustment of the second position.

[0010] Further, the laser tracker, the sensor module, the robot, the actuator group, the nozzle mounting seat, and the supply system are respectively connected to the control unit to form their respective communication lines, so that the control unit receives and sends signals through the corresponding communication lines.

[0011] A magnetorheological polishing method for adjusting the position of a supply system, based on the magnetorheological polishing equipment based on sensor adjustment provided by the present invention, includes the following steps: A1: Use a laser tracker to obtain the first coordinate of the sensor module and the second coordinate of the working point of the polishing wheel; through the two coordinates, use the coordinate relationship module to calculate the coordinate conversion relationship; A2: Use the coordinate relationship module to convert the first theoretical coordinate of the working point of the polishing wheel at different polishing trajectory points into the second theoretical coordinate of the sensor module through the coordinate conversion relationship, and obtain the theoretical straight-line distance according to the current second theoretical coordinate and the previous second theoretical coordinate; A3: Use the coordinate relationship module to record the measurement result of the sensor module to obtain the actual straight-line distance; the actual straight-line distance and the theoretical straight-line distance are used by the coordinate relationship module to calculate the distance error; A4: Control the magnetorheological processing module to process the test optical element, and obtain the first conversion relationship through the conversion relationship module; A5: Set the distance error threshold, the regulation maximum value, and the maximum first position; according to the distance error, the distance error threshold, and the regulation maximum value, combine the first conversion relationship and the maximum first position to process the optical element to be processed, and perform real-time regulation on the first position through the real-time regulation module during the processing.

[0012] Further, in step A1, the laser tracker obtains the coordinates of no less than 4 positions on the sensor module through the target ball, and calculates the first coordinate through calculation ; The laser tracker obtains the coordinates of no less than 10 different positions on the outer surface of the polishing wheel through the target ball, and then calculates the center point coordinates of the polishing wheel , and the straight line passing through the center point coordinates is: ; Among them, The normal vector of the straight line representing the center point coordinates; By solving the spatial coordinates corresponding to the minimum value of the Z-axis coordinate in the following system of equations and using them as the second coordinates : ; Among them, Represents the radius of the polishing wheel; Obtain the coordinate conversion relationship from the second coordinates and the first coordinates: ; Among them, Represents the coordinate conversion relationship.

[0013] Furthermore, in step A2, the theoretical straight-line distance is obtained through the following formula: ; Among them, Represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, Represents the Z coordinate in the current second theoretical coordinates, Represents the Z coordinate in the previous second theoretical coordinates.

[0014] Furthermore, in step A3, the actual straight-line distance is obtained through the following formula: ; Among them, Represents the actual straight-line distance between the current polishing trajectory point and the previous polishing trajectory point; Represents the acceleration measured by the sensor module at the previous polishing trajectory point, Represents the speed measured by the sensor module at the previous polishing trajectory point, Represents the measurement time of the sensor module; and then the distance error is obtained through the following formula : .

[0015] Furthermore, step A4 specifically includes the following steps: A41: At different polishing gaps, keep the position of the nozzle orifice of the nozzle relative to the polishing wheel unchanged, separately change the first position, process at different positions of the test optical element, and calculate the volume removal rate of the removal function for each polishing trajectory point to obtain the fourth conversion relationship between the volume removal rate of the removal function and the first position: ; Among them, Represents the first position, Indicates the removal rate of the function volume removal Indicates the fourth conversion relationship; A42: Keep the first position unchanged, control the polishing wheel to process at different positions of the test optical element with different polishing gaps, and calculate the removal rate of the function volume of the removal function at each polishing trajectory point to obtain the fifth conversion relationship between the removal rate of the function volume removal and the polishing gap: ; Wherein, Indicates the polishing gap, Indicates the fifth conversion relationship; A43: According to the fourth conversion relationship and the fifth conversion relationship, obtain the first conversion relationship: ; Wherein, Indicates the first conversion relationship.

[0016] Further, in step A5, when the polishing wheel is located at the th polishing trajectory point, compare the current distance error with the distance error threshold : If , then do not adjust the current first position ; If , then adjust the current first position : If the current first position is less than the maximum first position , the current first position is adjusted according to the following formula:

[0017] If the current first position is greater than or equal to the maximum first position , the current first position is adjusted to .

[0018] A nozzle-adjusted magnetorheological polishing method, based on the sensor-adjusted magnetorheological polishing equipment provided by the present invention, includes the following steps: B1: Use a laser tracker to obtain the first coordinate of the sensor module and the second coordinate of the working point of the polishing wheel; through the two coordinates, use the coordinate relationship module to calculate the coordinate conversion relationship; B2: Using the coordinate relationship module, through the coordinate conversion relationship, convert the first theoretical coordinates of the working point of the polishing wheel at different polishing trajectory points into the second theoretical coordinates of the sensor module, and obtain the theoretical straight-line distance based on the current second theoretical coordinates and the previous second theoretical coordinates; B3: Use the coordinate relationship module to record the measurement results of the sensor module to obtain the actual straight-line distance; the distance error is calculated through the coordinate relationship module between the actual straight-line distance and the theoretical straight-line distance; B4: Control the magnetorheological machining module to machine the test optical element, and obtain the second conversion relationship through the conversion relationship module; B5: Set the distance error threshold, regulation maximum value, and maximum second position; according to the distance error, distance error threshold, and regulation maximum value, combined with the second conversion relationship and the maximum second position, machine the optical element to be machined, and perform real-time regulation on the nozzle through the real-time regulation module during the machining process.

[0019] Further, in step B1, the laser tracker obtains the coordinates of no less than 4 positions on the sensor module through the target ball, and calculates the first coordinates ; The laser tracker obtains the coordinates of no less than 10 different positions on the outer surface of the polishing wheel through the target ball, and then calculates the center point coordinates of the polishing wheel , the straight line passing through the center point coordinates is: ; Among them, represents the normal vector of the straight line of the center point coordinates; Obtain the spatial coordinates corresponding to the minimum value of the Z-axis coordinate in the following system of equations and use them as the second coordinates : ; Among them, represents the radius of the polishing wheel; Obtain the coordinate conversion relationship through the second coordinates and the first coordinates: ; Among them, represents the coordinate conversion relationship.

[0020] Further, in step B2, obtain the theoretical straight-line distance through the following formula:

[0021] Among them, represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, represents the Z coordinate in the current second theoretical coordinates, Represents the Z coordinate in the previous second theoretical coordinate.

[0022] Further, in step B3, the actual straight-line distance is obtained by the following formula: ; where represents the actual straight-line distance between the current polishing trajectory point and the previous polishing trajectory point; represents the acceleration measured by the sensor module at the previous polishing trajectory point, represents the velocity measured by the sensor module at the previous polishing trajectory point, represents the measurement time of the sensor module; the distance error is obtained by the following formula : .

[0023] Further, step B4 includes the following steps: B41: At different polishing clearances, change the second position, process at different positions of the test optical element with different polishing clearances, and calculate the volume removal rate of the removal function for each polishing trajectory point at different polishing clearances to obtain the sixth conversion relationship between the volume removal rate of the removal function and the second position: ; where represents the second position, represents the volume removal rate of the removal function, represents the sixth conversion relationship; B42: Control the robot to drive the polishing wheel to process at different positions of the test optical element with different polishing clearances, and calculate the volume removal rate of the removal function for each polishing trajectory point to obtain the seventh conversion relationship between the volume removal rate of the removal function and the polishing clearance: ; where represents the polishing clearance, represents the seventh conversion relationship; B44: Obtain the second conversion relationship according to the sixth conversion relationship and the seventh conversion relationship, that is: ; where represents the second conversion relationship.

[0024] Further, in step B5, when the polishing wheel is at the th polishing trajectory point, compare the distance error with the distance error threshold : If , then do not perform on the current second position Perform regulation; If , then perform regulation on the current second position : If the current second position is less than the maximum second position , the current second position is regulated according to the following formula: ; If the current second position is greater than or equal to the maximum second position , the current second position is adjusted to .

[0025] A magnetorheological polishing method for actuator adjustment, based on the magnetorheological polishing equipment with sensor adjustment provided by the present invention, includes the following steps: C1: Use a laser tracker to obtain the first coordinate of the sensor module and the second coordinate of the working point of the polishing wheel; through the two coordinates, calculate the coordinate transformation relationship using the coordinate relationship module; C2: Use the coordinate relationship module to convert the first theoretical coordinate of the working point of the polishing wheel at different polishing trajectory points into the second theoretical coordinate of the sensor module through the coordinate transformation relationship, and obtain the theoretical straight-line distance based on the current second theoretical coordinate and the previous second theoretical coordinate; C3: Use the coordinate relationship module to record the measurement results of the sensor module to obtain the actual straight-line distance; calculate the distance error between the actual straight-line distance and the theoretical straight-line distance through the coordinate relationship module; C4: Set the distance error threshold and the maximum regulation value; determine the output displacement of the actuator group during processing according to the distance error, the distance error threshold, and the maximum regulation value, and process the optical element to be processed.

[0026] Further, in step C1, the laser tracker obtains the coordinates of not less than 4 positions on the sensor module through the target ball, and calculates the first coordinate ; The laser tracker obtains the coordinates of not less than 10 different positions on the outer surface of the polishing wheel through the target ball, and then calculates the center point coordinates of the polishing wheel , and the straight line passing through the center point coordinates is: ; wherein, represents the normal vector of the straight line of the center point coordinates; Solve the spatial coordinates corresponding to the minimum Z-axis coordinate in the following system of equations and use them as the second coordinate : ; Among them, represents the radius of the polishing wheel; The coordinate transformation relationship is obtained from the second coordinate and the first coordinate: ; Among them, represents the coordinate transformation relationship.

[0027] Furthermore, in step C2, the theoretical straight-line distance is obtained by the following formula: ; Among them, represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, represents the Z coordinate in the current second theoretical coordinate, represents the Z coordinate in the previous second theoretical coordinate.

[0028] Furthermore, in step C3, the actual straight-line distance is obtained by the following formula: ; Among them, represents the actual straight-line distance between the current polishing trajectory point and the previous polishing trajectory point; represents the acceleration measured by the sensor module at the previous polishing trajectory point, represents the speed measured by the sensor module at the previous polishing trajectory point, represents the measurement time of the sensor module; and then the distance error is obtained by the following formula: ; Among them, represents the distance error.

[0029] Furthermore, in step C4, when the polishing wheel is at the th polishing trajectory point, the current distance error , the distance error threshold and the regulation maximum value are compared: When , the actuator group is not regulated; When , the actuator group is regulated: If , the output displacement of the actuator group is the current distance error , and the current polishing gap , among which, represents the polishing gap when the polishing wheel is at the th polishing trajectory point; If The output displacement of the actuator group is the regulated maximum value At this time, the current polishing gap . In step A2, it is obtained by the following formula: ; Wherein, represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, represents the Z coordinate in the current second theoretical coordinate, represents the Z coordinate in the previous second theoretical coordinate.

[0030] Compared with the prior art, the present invention can achieve the following beneficial effects: In the magnetorheological polishing device and method based on sensor adjustment according to the present invention, through the cooperation of a laser tracker and a sensor module to measure the real-time six-dimensional pose information of the robot during the processing, the supply system, nozzle and actuator in the magnetorheological processing module are regulated in real time, so as to realize the real-time constant control of the change of the removal function under the coupling of multiple factors during the processing of the optical element to be processed; at the same time, the acquisition of the pose information does not need to rely on the actual processing process, and the pose error information of the processing equipment can be obtained during the processing trial operation link (no magnetorheological fluid is introduced in this link and no processing effect is generated), and it is not necessary to place the measuring equipment at the lowest point of the polishing wheel, which will not affect the actual processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The attached drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a schematic structural diagram of the magnetorheological polishing device based on sensor adjustment according to an embodiment of the present invention from one perspective; Figure 2 is a schematic structural diagram of the magnetorheological polishing device based on sensor adjustment according to an embodiment of the present invention from another perspective; Figure 3 is a schematic structural diagram of the actuator according to an embodiment of the present invention; Figure 4 is a schematic structural diagram of the supply system according to an embodiment of the present invention; Figure 5 is a schematic structural diagram of the liquid pump according to an embodiment of the present invention; Figure 6 is a schematic structural diagram of the nozzle mounting seat according to an embodiment of the present invention.

[0032] Description of the reference numerals: 1. Robot; 2. Sensor module; 3. Laser tracker; 4. Control unit; 5. High-frequency actuator; 6. Test bench; 7. Optical element to be processed; 8. Test optical element; 9. Target ball; 10. Polishing wheel; 11. Supply system; 12. Nozzle; 13. Transmission belt; 14. Polishing motor; 15. Magnet; 16. Magnetorheological mounting bracket; 17. Nozzle mounting seat; 18. Liquid pump; 19. Supply mounting bracket; 20. Supply motor; 21. Lead screw; 22. Mounting fixing plate; 23. Slide rail; 24. Liquid pump body; 25. Cooling chamber; 26. Magnetorheological fluid storage chamber; 27. Cooling water inlet; 28. Magnetorheological fluid inlet; 29. Cooling water outlet; 30. Magnetorheological fluid outlet; 31. Nozzle support frame; 32. Nozzle adjustment motor; 33. Fixed frame; 34. Push rod; 35. Slide block; 36. Arc slide rail; 37. Transition plate; 38. Cylinder block; 39. Chamber A; 40. Chamber B; 41. Oil scraping ring; 42. Connecting plate; 43. Moving piston. Detailed implementation manner

[0033] In order to make the objectives, technical solutions and advantages of the present invention clearer, the following further elaborates on the present invention in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention.

[0034] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0035] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0036] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "linkage" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0038] As Figure 1 and Figure 2 shown, the magnetorheological polishing equipment based on sensor adjustment described in the embodiment of the present invention includes a robot 1, a magnetorheological processing module, a sensor module 2, a laser tracker 3, a control unit 4, and an actuator group. The actuator group is arranged at the free end of the robot 1; the magnetorheological processing module is installed at the output end of the actuator group, so that the robot 1 and the actuator group drive the magnetorheological processing module to process the optical element 7 to be processed or the test optical element 8 placed on the test bench 6. The sensor module 2 is arranged on the magnetorheological processing module. The laser tracker 3 cooperates with the target ball 9 arranged on the magnetorheological processing module to measure the spatial coordinates of the working point of the sensor module 2 and the polishing wheel 10 in the magnetorheological processing module. In the embodiment of the present invention, the laser tracker 3 is installed on one side of the test bench 6, and the position of the target ball 9 is adjusted correspondingly according to the needs of the measurement object. For example, when the spatial coordinates of the sensor module 2 need to be measured, the target ball 9 is installed at the corresponding position of the sensor module 2. When the polishing wheel 10 needs to be measured, the target ball 9 is installed at the corresponding position of the polishing wheel 10.

[0039] In the embodiment of the present invention, the actuator group is composed of two cascaded high-frequency actuators 5, that is, one high-frequency actuator 5 is installed at the output end of the other high-frequency actuator 5, so that the total output displacement of the actuator group is the sum of the output displacements of the two high-frequency actuators 5. In the embodiment of the present invention, the high-frequency actuator 5 preferably adopts the SG model hydrostatic linear cylinder of Jilin Huakong Test Instrument Co., Ltd. The structure of each high-frequency actuator 5 is as Figure 3 shown, including a transition plate 37, a cylinder block 38, an A chamber 39, a B chamber 40, an oil scraper ring 41, a connecting plate 42, and a moving piston 43. The transition plate 37 is used to connect the free-end flange of the robot 1 and the cylinder block 38 of the high-frequency actuator 5. The A chamber 39 and the B chamber 40 are used for the inlet and outlet of hydraulic oil. The oil scraper ring 41 is used to prevent the hydraulic oil from flowing out of the cylinder block 38. The moving piston 43 is used for position output. The connecting plate 42 is used to connect with the magnetorheological processing module or another high-frequency actuator 5, and then output displacement to the magnetorheological processing module or another high-frequency actuator 5.

[0040] Inside the control unit 4, there are a coordinate relationship module, a conversion relationship module, a machining program module, and a real-time regulation module. Among them, the coordinate relationship module is used to integrate and calculate the spatial coordinates collected by the laser tracker 3 and the position information collected by the sensor module 2, and output the integrated position information. The conversion relationship module fits the first position of the supply system 11 in the magnetorheological machining module with the polishing gap of the polishing wheel 10 to obtain a first conversion relationship, and fits the second position of the nozzle 12 in the magnetorheological machining module with the polishing gap to obtain a second conversion relationship. In the embodiment of the present invention, the first position of the supply system 11 is the vertical distance between the nozzle orifice of the nozzle 12 and the working point of the supply system 11 (i.e., the liquid outlet of the supply system 11). When the vertical distance between the nozzle orifice of the nozzle 12 and the working point of the supply system 11 changes, the flow rate will change, and thus the removal function will change. It is stipulated that the second position of the nozzle 12 is the vertical distance between the nozzle orifice of the nozzle 12 and the working point of the polishing wheel 10 (i.e., the lowest point when the polishing wheel 10 contacts the optical element to be processed 7 or the test optical element 8). The machining program module obtains a machining program according to the removal function generated when the magnetorheological machining equipment processes the optical element, and imports the machining program into the magnetorheological machining equipment. The real-time regulation module adjusts the supply system 11 according to the integrated position information and the first conversion relationship, or adjusts the nozzle 12 according to the integrated position information and the second conversion relationship, or adjusts the actuator group according to the integrated position information, so as to keep the removal function stable when processing the optical element to be processed 7 or the test optical element 8.

[0041] In the embodiment of the present invention, the structure of the supply system 11 is as Figures 1 to 4As shown in the figure, it includes a liquid pump 18, a supply mounting bracket 19, a supply motor 20 and a lead screw 21. The lead screw 21 and the nut with balls thereon together form a ball screw. Among them, the supply motor 20 and the lead screw 21 are mounted on the supply mounting bracket 19, and the output end of the supply motor 20 is connected to one end of the lead screw 21, so that the supply motor 20 drives the lead screw 21 to rotate. The liquid pump 18 is arranged on the nut of the lead screw 21, so that the lead screw 21 drives the liquid pump 18 to move, thereby changing the first position. The liquid pump 18 conveys the magnetorheological fluid to the nozzle 12 through a pipeline. In the embodiment of the present invention, the liquid pump 18 is mounted on the nut of the lead screw 21 through a mounting fixing plate 22, so that the lead screw 21 drives the liquid pump 18 to move through the mounting fixing plate 22. In addition, in order to prevent the mounting fixing plate 22 from driving the liquid pump 18 to have a lateral offset in the embodiment of the present invention, preferably, on the supply mounting bracket 19, two slide rails 23 are arranged parallel to the lead screw 21, and the two slide rails 23 are respectively located on both sides of the lead screw 21. The mounting fixing plate 22 is mounted on the nut of the lead screw 21 and the sliders on the two slide rails 23. When the supply motor 20 drives the lead screw 21 to rotate during the processing, the lead screw 21 cooperates with the two slide rails 23 to jointly pull the mounting fixing plate 22, and then drives the liquid pump 18 to move along the lead screw 21.

[0042] The structure of the liquid pump 18 in the embodiment of the present invention is as Figure 5 shown, and it includes a liquid pump body 24, a cooling chamber 25 and a magnetorheological fluid storage chamber 26. The liquid pump body 24 selects the CFLC vertical multi-stage pump of Shanghai Orient Pump Industry Co., Ltd. and is used to supply the magnetorheological fluid; the cooling chamber 25 is mainly used to store cooling water and cool down the magnetorheological fluid; the magnetorheological fluid storage chamber 26 is mainly used to store the magnetorheological fluid. When the liquid pump 18 works, the cooling water enters the cooling chamber 25 from the cooling water inlet 27, and the magnetorheological fluid enters the liquid pump body 24 from the magnetorheological fluid inlet 28 through the magnetorheological fluid storage chamber 26; the cooling water cools down the magnetorheological fluid in the cooling chamber 25 and then is discharged from the cooling water outlet 29; the cooled magnetorheological fluid is output from the magnetorheological fluid outlet 30 and conveys the magnetorheological fluid to the nozzle 12 through a pipeline. At this time, the outlet of the supply system 11 is the magnetorheological fluid outlet 30. Further, the first position of the supply system 11 is the vertical distance between the nozzle orifice of the nozzle 12 and the magnetorheological fluid outlet 30. The liquid pump speed of the liquid pump 18 is adjusted by a motor. When the motor speed changes, the liquid pump 18 changes the liquid pump speed.

[0043] The magnetorheological processing module further includes a conveyor belt 13, a polishing motor 14, a magnet 15, and a magnetorheological mounting bracket 16. The magnetorheological mounting bracket 16 is fixed to the output end of the actuator group, and the polishing wheel 10 is mounted on the magnetorheological mounting bracket 16. The polishing motor 14 is fixed to the magnetorheological mounting bracket 16, and the output end of the polishing motor 14 is connected to the bearing of the polishing wheel 10 through the conveyor belt 13, so that the polishing motor 14 controls the rotation of the polishing wheel 10. In the embodiment of the present invention, the manner in which the polishing motor 14 drives the polishing wheel 10 to rotate can refer to the invention patent application with the Chinese patent publication number CN118322074A, the publication date of July 12, 2024, and the patent name of "Self-rotating Polishing Module Processing System". The nozzle 12 is mounted on the magnetorheological mounting bracket 16 along the rotation direction of the polishing wheel 10 through a nozzle mounting seat 17. The nozzle mounting seat 17 can adjust the mounting angle of the nozzle 12, thereby changing the second position of the nozzle orifice of the nozzle 12. The supply system 11 conveys magnetorheological fluid to the nozzle 12 through a pipeline. The magnet 15 is mounted on the magnetorheological mounting bracket 16 and near the working point of the polishing wheel 10, so that the magnetorheological fluid is affected by the magnetic field intensity of the magnet 15 to change the stiffness of the magnetorheological fluid, and the polishing wheel 10 processes the optical element to be processed 7 or the test optical element 8 with the magnetorheological fluid with a certain stiffness as the medium. The sensor module 2 is arranged on the magnetorheological mounting bracket 16, and the laser tracker 3 measures the spatial coordinates of the sensor module 2 through the target ball 9.

[0044] The structure of the nozzle mounting seat 17 is as Figure 6 shown. Among them Figure 6 Figure (a) shows a schematic structural diagram when the nozzle 12 is mounted on the nozzle mounting seat 17, Figure 6 and figure (b) shows a schematic structural diagram when the nozzle 12 is not mounted on the nozzle mounting seat 17. In the nozzle mounting seat 17, the fixing frame 33 is an L-shaped structure and is fixed to the magnetorheological mounting bracket 16, and an arc-shaped slide rail 36 is arranged on the inner side wall of the fixing frame 33. The nozzle adjustment motor 32 is mounted on the magnetorheological mounting bracket 16. One end of the push rod 34 passes through the bottom edge of the fixing frame 33 and is connected to the output end of the nozzle adjustment motor 32, so that the nozzle adjustment motor 32 drives the push rod 34, and then the push rod 34 pushes the slider 35 on the arc-shaped slide rail 36 to move along the arc-shaped slide rail 36. One end of the nozzle support frame 31 is fixed to the slider 35, and the nozzle 12 is mounted on the other end of the nozzle support frame 31. When controlling the nozzle mounting seat 17 to adjust the position of the nozzle 12, the nozzle adjustment motor 32 outputs displacement, so that the push rod 34 pushes the slider 35, and then the nozzle support frame 31 drives the nozzle 12 to move, thereby completing the adjustment of the second position of the nozzle 12.

[0045] The robot 1, the sensor module 2, the laser tracker 3, the supply system 11, the actuator group and the nozzle mounting base 17 are respectively connected to the control unit 4 to form their respective communication lines, enabling the control unit 4 to receive and send signals through the corresponding communication lines. Specifically, the control unit 4 is communicatively connected to the supply motor 20 through a line. During operation, the control unit 4 gives a control command to the supply motor 20, and the supply motor 20 drives the lead screw 21 to rotate. The rotating lead screw 21 drives the mounting fixed plate 22 to move, thereby changing the vertical position of the liquid pump 18, and thus changing the first position of the supply system 11; the control unit 4 controls the oil pressure of the hydraulic oil in the high-frequency actuator 5, and then controls the expansion and contraction of the moving piston 43 to achieve the position regulation of the magnetorheological processing module, thereby changing the output of the actuator group; the control unit 4 controls the nozzle adjustment motor 32, and then changes the position of the nozzle support frame 31. The nozzle support frame 31 moves along the arc slide rail 36, thereby changing the second position of the nozzle 12.

[0046] Since a strong magnetic field region is generated around the polishing wheel 10 during the polishing operation, the communication lines avoid the strong magnetic field region.

[0047] Based on the magnetorheological polishing device with sensor adjustment described in the embodiments of the present invention, the embodiments of the present invention also provide a magnetorheological polishing method with sensor adjustment, including a magnetorheological polishing method for supply system position adjustment, a magnetorheological polishing method for nozzle adjustment, and a magnetorheological polishing method for actuator adjustment.

[0048] Specific Embodiment 1: The magnetorheological polishing method for supply system position adjustment described in this specific embodiment is based on the magnetorheological polishing device with sensor adjustment described in the embodiments of the present invention, in combination with Figure 1 and Figure 2 , and Figure 4 and Figure 5 , and includes the following steps: A1: Use the laser tracker to obtain the first coordinate of the sensor module and the second coordinate of the working point of the polishing wheel; through the two coordinates, use the coordinate relationship module to calculate the coordinate conversion relationship.

[0049] In step A1, in this specific embodiment, a cylindrical or cuboid acceleration sensor is used as the sensor module 2, and the laser tracker 3 is used in cooperation with the target ball 9 to obtain the coordinates of no less than 4 positions on the sensor module 2, and the first coordinate is obtained through calculation .

[0050] For the cylindrical acceleration sensor, place the target ball 9 at at least 3 different positions on the cylindrical bottom of the cylindrical acceleration sensor and use the laser tracker 3 to measure its spatial coordinates. Utilize the circle fitting function of the laser tracker 3 (this function is a basic function of the laser tracker) to obtain the X-Y coordinates of the cylindrical acceleration sensor , based on the Z-axis coordinates of the target ball 9 at different positions calculate the Z-axis coordinate where the bottom surface of the cylindrical acceleration sensor is located, , where k represents the number of measurement points. Place the target ball 9 at at least 3 different positions on the top of the cylindrical acceleration sensor and use the laser tracker 3 to measure its spatial coordinates. Based on the Z-axis coordinates of the target ball 9 at different positions calculate the Z-axis coordinate where the top surface of the cylindrical acceleration sensor is located, , where j represents the number of measurement points, and the first coordinate of the cylindrical acceleration sensor is , and r is the radius of the target ball 9. In this specific embodiment, for the cylindrical acceleration sensor, 10 different positions are selected at its bottom and top respectively.

[0051] For the cuboid acceleration sensor, place the target ball 9 at the bottom of the four sides of the cuboid acceleration sensor respectively and use the laser tracker 3 to measure its spatial coordinates. Measure the coordinates of one target ball 9 point at the bottom of each side, and obtain the bottom coordinates of the four sides of the cuboid acceleration sensor as 、 、 、 , and solve for the X-Y axis coordinates of the cuboid acceleration sensor as , based on the Z-axis coordinates of the target ball 9 at different positions calculate the Z-axis coordinate where the bottom surface of the cuboid acceleration sensor is located, and obtain ; place the target ball 9 at at least 3 different positions on the top of the cuboid acceleration sensor and use the laser tracker 3 to measure its spatial coordinates. Based on the Z-axis coordinates of the target ball 9 at different positions calculate the Z-axis coordinate where the top surface of the cuboid acceleration sensor is located, , and the first coordinate of the cuboid acceleration sensor is . In this specific embodiment, for the cuboid acceleration sensor, 10 different positions are selected at its top.

[0052] The laser tracker 3 obtains the coordinates of no less than 10 different positions on the outer surface of the polishing wheel 10 through the target ball 9 (obtain the coordinates of 10 different positions in this specific embodiment), and the center point coordinates of the polishing wheel 10 can be obtained through the coordinate calculation function of the laser tracker 3 itself , and the straight line passing through the center point coordinates is obtained through the teach pendant of the robot 1 as: ; Among them, The normal vector of the straight line representing the center point coordinates; By solving the spatial coordinates corresponding to the minimum value of the Z-axis coordinate in the following system of equations and using them as the second coordinate : ; Among them, Represents the radius of the polishing wheel; Obtain the coordinate conversion relationship from the second coordinate and the first coordinate: ; Among them, Represents the coordinate conversion relationship.

[0053] A2: Using the coordinate relationship module, through the coordinate conversion relationship, convert the first theoretical coordinates of the working points of the polishing wheel 10 at different polishing trajectory points into the second theoretical coordinates of the sensor module 2, and obtain the theoretical straight-line distance based on the current second theoretical coordinates and the previous second theoretical coordinates. In this specific embodiment, the theoretical straight-line distance is the distance in the Z-axis direction.

[0054] In step A2, the theoretical straight-line distance is obtained through the following formula: ; Among them, Represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, Represents the Z coordinate in the current second theoretical coordinates, Represents the Z coordinate in the previous second theoretical coordinates.

[0055] A3: Using the coordinate relationship module to record the measurement results of the sensor module 2 to obtain the actual straight-line distance; the actual straight-line distance and the theoretical straight-line distance are used by the coordinate relationship module to calculate the distance error. In this specific embodiment, the actual straight-line distance is the distance in the Z-axis direction.

[0056] In step A3, the actual straight-line distance is obtained through the following formula : ; Among them, Represents the actual straight-line distance between the current polishing trajectory point and the previous polishing trajectory point; Represents the acceleration measured by the sensor module 2 at the previous polishing trajectory point, Represents the speed measured by the sensor module 2 at the previous polishing trajectory point, Represents the measurement time of the sensor module 2; and then the distance error is obtained through the following formula : 。

[0057] A4: Control the magnetorheological machining module to machine the test optical element 8, and obtain the first conversion relationship through the conversion relationship module.

[0058] Step A4 specifically includes the following steps: A41: At different polishing clearances, keep the position of the nozzle orifice of the nozzle 12 relative to the polishing wheel 10 unchanged, separately change the first position, machine at different positions of the test optical element 8, and calculate the volume removal rate of the removal function for each polishing trajectory point to obtain the fourth conversion relationship between the volume removal rate of the removal function and the first position: ; Among them, represents the first position, represents the volume removal rate of the removal function, represents the fourth conversion relationship; in this specific embodiment, specifically, fixed-point machining is performed for a period of time at different positions of the test optical element 8; A42: Control the polishing wheel 10 to machine at different positions of the test optical element 8 with different polishing clearances, and calculate the volume removal rate of the removal function for each polishing trajectory point to obtain the fifth conversion relationship between the volume removal rate of the removal function and the polishing clearance: ; Among them, represents the polishing clearance, represents the fifth conversion relationship; in this specific embodiment, specifically, control the polishing wheel 10 to perform fixed-point machining for a period of time at different positions of the test optical element 8 with different polishing clearances; A43: According to the fourth conversion relationship and the fifth conversion relationship, obtain the first conversion relationship: ; Among them, represents the first conversion relationship.

[0059] A5: Set the distance error threshold, regulation maximum value, and maximum first position; according to the distance error, distance error threshold, and regulation maximum value, combined with the first conversion relationship and the maximum first position, machine the optical element 7 to be processed, and perform real-time regulation on the first position through the real-time regulation module during the machining process. In this specific embodiment, the maximum first position is defined as the maximum vertical distance between the nozzle orifice of the nozzle 12 and the working point of the supply system 11. The distance error threshold, regulation maximum value, and maximum liquid pump speed are adaptively set according to the actual situation, and this specific embodiment does not limit this.

[0060] In step A5, when the polishing wheel 10 is at the th polishing trajectory point, compare the current distance error with the distance error threshold : If , then do not adjust the current first position ; If , then adjust the current first position : If the current first position is less than the maximum first position , that is, , the current first position is adjusted according to the following formula: ; If the current first position is greater than or equal to the maximum first position , that is, , the current first position is adjusted to .

[0061] In this specific embodiment, the discrete data volume corresponding to different polishing gaps obtained through experiments is limited, and the actual measured polishing gap during the processing may not be equal to the polishing gap data value obtained through experiments. The solution is to use the closest data, that is, the rounding principle. For example: The fourth conversion relationship between the material removal rate MRR of the removal function and the first position corresponding to the polishing gaps of 1 mm and 2 mm is obtained through experiments, and then the corresponding first conversion relationship is obtained. However, the polishing gap during the processing is 1.6 mm. At this time, the fifth conversion relationship is used to calculate the material removal rate MRR of 2 mm.

[0062] Specific embodiment 2: The nozzle-adjusted magnetorheological polishing method described in this specific embodiment is based on the sensor-adjusted magnetorheological polishing equipment described in the embodiment of the present invention, and combines Figure 1 , Figure 2 and Figure 6 , and includes the following steps: B1: Use the laser tracker 3 to obtain the first coordinate of the sensor module 2 and the second coordinate of the working point of the polishing wheel 10; through the two coordinates, calculate the coordinate conversion relationship using the coordinate relationship module.

[0063] B2: Using the coordinate relationship module, through the coordinate conversion relationship, convert the first theoretical coordinates of the working point of the polishing wheel 10 at different polishing trajectory points into the second theoretical coordinates of the sensor module 2, and obtain the theoretical straight-line distance based on the current second theoretical coordinates and the previous second theoretical coordinates. In this specific embodiment, the theoretical straight-line distance is the distance in the Z-axis direction.

[0064] B3: Use the coordinate relationship module to record the measurement results of the sensor module 2 to obtain the actual straight-line distance; the distance error is calculated through the coordinate relationship module between the actual straight-line distance and the theoretical straight-line distance.

[0065] The content of steps B1 to B3 in this specific embodiment is the same as the content of steps A1 to A3 in specific embodiment 1, and will not be elaborated here.

[0066] B4: Control the magnetorheological processing module to process the test optical element 8, and obtain the second conversion relationship through the conversion relationship module.

[0067] Step B4 includes the following steps: B41: At different polishing gaps, change the second position of the nozzle 12, perform processing at different positions of the test optical element 8 with different polishing gaps, and calculate the volume removal rate of the removal function for each polishing trajectory point to obtain the sixth conversion relationship between the volume removal rate of the removal function and the second position of the nozzle 12: ; Wherein, represents the second position of the nozzle 12, represents the volume removal rate of the removal function, represents the sixth conversion relationship; in this specific embodiment, specifically perform fixed-point processing for a period of time at different positions of the test optical element 8 with different polishing gaps; B42: Control the robot 1 to drive the polishing wheel 10 to perform processing at different positions of the test optical element 8 with different polishing gaps, and calculate the volume removal rate of the removal function for each polishing trajectory point to obtain the seventh conversion relationship between the volume removal rate of the removal function and the polishing gap: ; Wherein, represents the polishing gap, represents the eighth conversion relationship; in this specific embodiment, specifically control the polishing wheel 10 to perform fixed-point processing for a period of time on the test optical element 8 with different polishing gaps; B44: Obtain the second conversion relationship according to the sixth conversion relationship and the seventh conversion relationship, that is: ; Wherein, Represents the second conversion relationship.

[0068] B5: Set the distance error threshold, regulation maximum value, and maximum second position; according to the distance error, distance error threshold, and regulation maximum value, combine the second conversion relationship and the maximum second position to process the optical element 7 to be processed, and perform real-time regulation on the nozzle 12 through the real-time regulation module during the processing. The distance error threshold, regulation maximum value, and maximum second position are adaptively set according to the actual situation, and this specific embodiment does not limit this.

[0069] When the polishing wheel 10 is at the th polishing trajectory point, compare the current distance error with the distance error threshold : If , then do not regulate the current second position ; If , then regulate the current second position : If the current second position is less than the maximum second position , that is, , the current second position is regulated according to the following formula: ; If the current second position is greater than or equal to the maximum second position , that is, , the current second position is adjusted to .

[0070] In this specific embodiment, the discrete data volume corresponding to different polishing gaps obtained through experiments is limited, and the polishing gap actually measured during the processing may not be equal to the polishing gap data value obtained through experiments. The solution is to use the closest data, that is, the rounding principle. For example: The sixth conversion relationship between the material removal rate MRR of the removal function and the second position corresponding to the polishing gaps of 1 mm and 2 mm is obtained through experiments, and then the corresponding second conversion relationship is obtained. However, the polishing gap during the processing is 1.6 mm. At this time, the seventh conversion relationship is used to calculate the material removal rate MRR of 2 mm. between them, and then the corresponding second conversion relationship is obtained. However, the polishing gap during the processing is 1.6 mm. At this time, the seventh conversion relationship is used to calculate the material removal rate MRR of 2 mm.

[0071] Specific Embodiment 3: The magnetorheological polishing method for actuator adjustment described in this specific embodiment is based on the magnetorheological polishing equipment adjusted based on sensors described in the embodiments of the present invention, combined with Figures 1 to 3 , and includes the following steps: C1: Use the laser tracker 3 to obtain the first coordinate of the sensor module 2 and the second coordinate of the working point of the polishing wheel 10; use the coordinate relationship module to calculate the coordinate conversion relationship through the two coordinates.

[0072] C2: Using the coordinate relationship module, through the coordinate conversion relationship, the first theoretical coordinate of the working point of the polishing wheel 10 at different polishing trajectory points is converted into the second theoretical coordinate of the sensor module 2, and the theoretical straight-line distance is obtained based on the current second theoretical coordinate and the previous second theoretical coordinate.

[0073] C3: Use the coordinate relationship module to record the measurement results of sensor module 2 to obtain the actual straight-line distance; the actual straight-line distance and the theoretical straight-line distance are calculated through the coordinate relationship module to obtain the distance error.

[0074] The contents of steps C1 to C3 in this specific embodiment are consistent with the contents of steps A1 to A3 in specific embodiment 1, and are not repeated here.

[0075] C4: Setting a distance error threshold and a maximum control value. Based on the distance error, the distance error threshold, and the maximum control value, the output displacement of the actuator assembly is controlled during the machining process, and the optical element 7 to be machined is machined. The distance error threshold and the maximum control value are adaptively set based on actual conditions and are not limited in this embodiment.

[0076] In step C4, when the polishing wheel 10 is at the When polishing trajectory points, the current distance error , distance error threshold and control the maximum value Compare: when , then the actuator group is not regulated; when , then the actuator group is regulated: like , the output displacement of the actuator group is the current distance error , that is, the sum of the output displacements of the two cascaded high-frequency actuators is the current distance error ,Right now: ; in, represents the sum of the output displacements of two cascaded high-frequency actuators, represents the output displacement of one of the cascaded high-frequency actuators, Represents the output displacement of another cascaded high-frequency actuator. At this time, the current polishing gap for: ; in, represents the initially set polishing gap; the initial polishing gap It is also adaptively set according to the actual situation, and this specific embodiment does not limit it; If , the output displacement of the actuator group is the maximum regulation value , that is, the sum of the output displacements of two cascaded high-frequency actuators is the current distance error , that is: ; At this time, the current polishing gap is: .

[0077] The fitting process in the above specific embodiment includes but is not limited to importing discrete data into Matlab software and completing data fitting with the polyfit fitting instruction of Matlab software to solve their respective conversion relationships; The Polyfit fitting instruction is a basic general instruction of matlab software. In this way, the corresponding relationship and the corresponding function curve can be more intuitively seen.

[0078] It should be understood that various forms of processes shown above can be used, reordering, adding or deleting steps. For example, the steps recorded in the disclosure of the present invention can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solution disclosed in the present invention can be achieved, and this is not limited herein.

[0079] The above specific implementation manners do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A magnetorheological polishing device based on sensor adjustment, characterized in that: It includes a laser tracker, a control unit, an actuator group, a robot, a magnetorheological machining module and a sensor module; wherein, the actuator group is arranged at the free end of the robot, and the magnetorheological machining module is arranged at the output end of the actuator group, so that the robot and the actuator group drive the magnetorheological machining module to process the optical element; the sensor module is arranged on the magnetorheological machining module; the laser tracker cooperates with a target ball arranged on the magnetorheological machining module to measure the spatial coordinates of the working point of the polishing wheel in the sensor module and the magnetorheological machining module. The interior of the control unit includes: A coordinate relationship module, which is used to integrate and calculate the spatial coordinates collected by the laser tracker and the position information collected by the sensor module, and output the integrated position information. A conversion relationship module, which is used to fit the first position of the supply system in the magnetorheological machining module with the polishing gap of the polishing wheel to obtain a first conversion relationship, and fit the second position of the nozzle in the magnetorheological machining module with the polishing gap to obtain a second conversion relationship. A machining program module, which is used to obtain a machining program according to the removal function generated when the magnetorheological machining equipment processes the optical element, and import the machining program into the magnetorheological machining equipment. A real-time regulation module, which is used to adjust the actuator group according to the integrated position information, or adjust the supply system according to the integrated position information and the first conversion relationship, or adjust the nozzle according to the integrated position information and the second conversion relationship, so as to keep the removal function stable when processing the optical element.

2. The magnetorheological polishing device based on sensor adjustment according to claim 1, wherein: The magnetorheological machining module further includes a transmission belt, a polishing motor, a magnet and a magnetorheological mounting bracket; wherein, The magnetorheological mounting bracket is arranged at the output end of the actuator group, and the polishing wheel is arranged on the magnetorheological mounting bracket. The polishing motor is arranged on the magnetorheological mounting bracket and is connected to the bearing of the polishing wheel through the transmission belt, so that the polishing motor controls the polishing wheel to rotate. The nozzle is installed on the magnetorheological mounting bracket along the rotation direction of the polishing wheel through a nozzle mounting seat, and the nozzle mounting seat adjusts the installation angle of the nozzle, thereby changing the position of the nozzle orifice of the nozzle; the supply system conveys magnetorheological fluid to the nozzle. The magnet is arranged on the magnetorheological mounting bracket and close to the working point of the polishing wheel, so that the magnetorheological fluid is affected by the magnetic field intensity of the magnet to change the stiffness of the magnetorheological fluid. The sensor module is arranged on the magnetorheological mounting bracket, and the laser tracker measures the spatial coordinates of the sensor module through the target ball.

3. The magnetorheological polishing device based on sensor adjustment according to claim 2, wherein: The supply system includes a liquid pump, a supply mounting bracket, a supply motor and a lead screw; wherein, the supply motor and the lead screw are arranged on the supply mounting bracket, so that the supply motor drives the lead screw to rotate; the liquid pump is arranged on the nut of the lead screw, so that the lead screw drives the liquid pump to move, thereby changing the first position; the liquid pump conveys magnetorheological fluid to the nozzle through a pipeline.

4. The magnetorheological polishing device based on sensor adjustment according to claim 3, wherein: The nozzle mounting seat includes a fixing frame, a nozzle adjustment motor, a push rod, and a nozzle support frame. Among them, the fixing frame is arranged on the magnetorheological mounting frame, and arc-shaped slide rails are arranged on the inner side wall of the fixing frame. The nozzle adjustment motor is arranged on the magnetorheological mounting frame. One end of the push rod passes through the fixing frame and is connected to the nozzle adjustment motor, so that the nozzle adjustment motor pushes the slider on the arc-shaped slide rail through the push rod. One end of the nozzle support frame is arranged on the slider, and the nozzle is connected to the other end of the nozzle support frame, so that the nozzle adjustment motor pushes the slider through the push rod, and then the nozzle support frame drives the nozzle to move, thereby completing the adjustment of the second position.

5. The magnetorheological polishing device based on sensor adjustment according to claim 2, wherein: The laser tracker, the sensor module, the robot, the actuator group, the nozzle mounting seat, and the supply system are respectively connected to the control unit to form their respective communication lines, so that the control unit receives and sends signals through the corresponding communication lines.

6. A magnetorheological polishing method for adjusting the position of a supply system, based on the sensor-adjusted magnetorheological polishing equipment according to any one of claims 1 to 5, characterized in that: It includes the following steps: A1: Use the laser tracker to obtain the first coordinate of the sensor module and the second coordinate of the working point of the polishing wheel; through the two coordinates, use the coordinate relationship module to calculate the coordinate conversion relationship. A2: Use the coordinate relationship module to convert the first theoretical coordinate of the working point of the polishing wheel at different polishing trajectory points into the second theoretical coordinate of the sensor module through the coordinate conversion relationship, and obtain the theoretical straight-line distance according to the current second theoretical coordinate and the previous second theoretical coordinate. A3: Use the coordinate relationship module to record the measurement result of the sensor module to obtain the actual straight-line distance; the distance error is calculated through the coordinate relationship module between the actual straight-line distance and the theoretical straight-line distance. A4: Control the magnetorheological processing module to process the test optical element, and obtain the first conversion relationship through the conversion relationship module. A5: Set the distance error threshold, the regulation maximum value, and the maximum first position; according to the distance error, the distance error threshold, and the regulation maximum value, combine the first conversion relationship and the maximum first position to process the optical element to be processed, and perform real-time regulation on the first position through the real-time regulation module during the processing.

7. The magnetorheological polishing method for adjusting the position of the supply system according to claim 6, characterized in that: In step A1, the laser tracker obtains the coordinates of no less than 4 positions on the sensor module through the target ball, and calculates to obtain the first coordinate ; The laser tracker obtains the coordinates of no less than 10 different positions on the outer surface of the polishing wheel through the target ball, and then calculates the coordinates of the center point of the polishing wheel. , and the straight line passing through the coordinates of the center point is: ； Among them, The normal vector of the straight line representing the coordinates of the central point; By solving the spatial coordinates corresponding to the minimum value of the Z-axis coordinate in the following system of equations and taking them as the second coordinate : ； Among them, represents the radius of the polishing wheel; Obtain the coordinate conversion relationship through the second coordinate and the first coordinate: ； Among them, represents the coordinate conversion relationship.

8. The magnetorheological polishing method for adjusting the position of the supply system according to claim 7, characterized in that: In step A2, obtain the theoretical straight-line distance through the following formula: ； Among them, represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, represents the Z coordinate in the current second theoretical coordinate, represents the Z coordinate in the previous second theoretical coordinate.

9. The magnetorheological polishing method for adjusting the position of the supply system according to claim 8, characterized in that: In step A3, obtain the actual straight-line distance through the following formula: ； Among them, represents the actual straight-line distance between the current polishing trajectory point and the previous polishing trajectory point; represents the acceleration measured by the sensor module at the previous polishing trajectory point, represents the velocity measured by the sensor module at the previous polishing trajectory point, represents the measurement time of the sensor module; and then the distance error is obtained through the following formula : 。 10. The magnetorheological polishing method for adjusting the position of the supply system according to claim 9, characterized in that: Step A4 specifically includes the following steps: A41: Under different polishing clearances, keep the position of the nozzle orifice of the nozzle relative to the polishing wheel unchanged, separately change the first position, and perform processing at different positions of the test optical element, and calculate the volume removal rate of the removal function at each polishing trajectory point to obtain the fourth conversion relationship between the volume removal rate of the removal function and the first position. ； Among them, represents the first position, represents the volume removal rate of the removal function, represents the fourth conversion relationship; A42: Control the polishing wheel to perform point processing at different positions of the test optical element with different polishing gaps, calculate the volume removal rate of the removal function for each polishing trajectory point, and obtain the fifth conversion relationship between the volume removal rate of the removal function and the polishing gap: ； Among them, represents the polishing gap, represents the fifth conversion relationship; A43: Obtain the first conversion relationship according to the fourth conversion relationship and the fifth conversion relationship: ； Among them, represents the first conversion relationship.

11. The magnetorheological polishing method for adjusting the position of the supply system according to claim 9, characterized in that: In step A5, when the polishing wheel is located at the th polishing trajectory point, compare the current distance error with the distance error threshold as follows: If , then do not adjust the current first position . If , then adjust the current first position : If the current first position is less than the maximum first position then the current first position is adjusted according to the following formula: ； If the current first position is greater than or equal to the maximum first position , the current first position is adjusted to .

12. A nozzle-adjusted magnetorheological polishing method, based on the sensor-adjusted magnetorheological polishing equipment according to any one of claims 1 to 5, characterized in that: including the following steps: B1: Use the laser tracker to obtain the first coordinate of the sensor module and the second coordinate of the working point of the polishing wheel; through the two coordinates, use the coordinate relationship module to calculate the coordinate conversion relationship; B2: Use the coordinate relationship module, through the coordinate conversion relationship, convert the first theoretical coordinate of the working point of the polishing wheel at different polishing trajectory points into the second theoretical coordinate of the sensor module, and obtain the theoretical straight-line distance according to the current second theoretical coordinate and the previous second theoretical coordinate; B3: Use the coordinate relationship module to record the measurement result of the sensor module to obtain the actual straight-line distance; the distance error is calculated through the coordinate relationship module from the actual straight-line distance and the theoretical straight-line distance; B4: Control the magnetorheological processing module to process the test optical element, and obtain the second conversion relationship through the conversion relationship module; B5: Set the distance error threshold, regulation maximum value, and maximum second position; according to the distance error, the distance error threshold, and the regulation maximum value, combined with the second conversion relationship and the maximum second position, process the optical element to be processed, and perform real-time regulation on the nozzle through the real-time regulation module during the processing.

13. The nozzle-adjusted magnetorheological polishing method according to claim 12, characterized in that: In step B1, the laser tracker obtains the coordinates of no less than 4 positions on the sensor module through the target ball, and calculates to obtain the first coordinate ; The laser tracker obtains the coordinates of no less than 10 different positions on the outer surface of the polishing wheel through the target ball, and then calculates the coordinates of the center point of the polishing wheel , and the straight line passing through the coordinates of the center point is: ； Among them, The normal vector of the straight line representing the coordinates of the central point; By solving the spatial coordinates corresponding to the minimum value of the Z-axis coordinate in the following system of equations and using them as the second coordinate : ； Among them, represents the radius of the polishing wheel; Obtain the coordinate conversion relationship through the second coordinate and the first coordinate: ； Among them, represents the coordinate conversion relationship.

14. The nozzle-adjusted magnetorheological polishing method according to claim 13, characterized in that: In step B2, obtain the theoretical straight-line distance through the following formula: ； Among them, represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, represents the Z coordinate in the current second theoretical coordinate, represents the Z coordinate in the previous second theoretical coordinate.

15. The nozzle-adjusted magnetorheological polishing method according to claim 14, characterized in that: In step B3, obtain the actual straight-line distance through the following formula: ； Among them, represents the actual straight-line distance between the current polishing trajectory point and the previous polishing trajectory point; represents the acceleration measured by the sensor module at the previous polishing trajectory point, represents the velocity measured by the sensor module at the previous polishing trajectory point, represents the measurement time of the sensor module; the distance error is obtained by the following formula : 。 16. The nozzle-adjusted magnetorheological polishing method according to claim 15, characterized in that: Step B4 includes the following steps: B41: At different polishing gaps, change the second position, process at different positions of the test optical element with different polishing gaps, and calculate the volume removal rate of the removal function for each polishing trajectory point at different polishing gaps, and obtain the sixth conversion relationship between the volume removal rate of the removal function and the second position: ； Among them, represents the second position, represents the volume removal rate of the removal function, represents the sixth conversion relationship; B42: Control the robot to drive the polishing wheel to process at different positions of the test optical element with different polishing gaps, and calculate the volume removal rate of the removal function for each polishing trajectory point, and obtain the seventh conversion relationship between the volume removal rate of the removal function and the polishing gap: ； Among them, represents the polishing gap, represents the seventh conversion relationship; B44: Obtain the second conversion relationship according to the sixth conversion relationship and the seventh conversion relationship, that is: ； Among them, represents the second conversion relationship.

17. The nozzle-adjusted magnetorheological polishing method according to claim 16, characterized in that: In step B5, when the polishing wheel is at the th polishing trajectory point, compare the current distance error with the distance error threshold as follows: If , then the current second position is not regulated; If , then regulate the current second position : If the current second position is less than the maximum second position then the current second position is adjusted according to the following formula: ； If the current second position is greater than or equal to the maximum second position then the current second position is adjusted to .

18. A magnetorheological polishing method for actuator adjustment, according to the sensor-based magnetorheological polishing equipment described in any one of claims 1 to 5, characterized in that: including the following steps: C1: Use the laser tracker to obtain the first coordinate of the sensor module and the second coordinate of the working point of the polishing wheel; through the two coordinates, use the coordinate relationship module to calculate the coordinate conversion relationship; C2: Using the coordinate relationship module, through the coordinate conversion relationship, convert the first theoretical coordinates of the working point of the polishing wheel at different polishing trajectory points into the second theoretical coordinates of the sensor module, and obtain the theoretical straight-line distance based on the current second theoretical coordinates and the previous second theoretical coordinates; C3: Use the coordinate relationship module to record the measurement results of the sensor module to obtain the actual straight-line distance; the distance error is calculated through the coordinate relationship module between the actual straight-line distance and the theoretical straight-line distance; C4: Set the distance error threshold and the maximum regulation value; based on the distance error, the distance error threshold and the maximum regulation value, determine to regulate the output displacement of the actuator group during the processing and process the optical element to be processed.

19. The magnetorheological polishing method for actuator adjustment according to claim 18, characterized in that: In step C1, the laser tracker obtains the coordinates of no less than 4 positions on the sensor module through the target ball, and calculates to obtain the first coordinate ; The laser tracker obtains the coordinates of no less than 10 different positions on the outer surface of the polishing wheel through the target ball, and then calculates the coordinates of the center point of the polishing wheel , and the straight line passing through the coordinates of the center point is: ； Among them, The normal vector of the straight line representing the coordinates of the center point; By solving the spatial coordinates corresponding to the minimum value of the Z-axis coordinate in the following system of equations and using them as the second coordinate : ； Among them, represents the radius of the polishing wheel; Obtain the coordinate conversion relationship through the second coordinate and the first coordinate: ； Among them, represents the coordinate conversion relationship.

20. The magnetorheological polishing method for actuator adjustment according to claim 19, wherein: In step C2, obtain the theoretical straight-line distance through the following formula: Among them, represents the theoretical straight-line distance between the current polishing trajectory point and the previous polishing trajectory point, represents the Z coordinate in the current second theoretical coordinate, represents the Z coordinate in the previous second theoretical coordinate.

21. The magnetorheological polishing method for actuator adjustment according to claim 20, characterized in that: In step C3, obtain the actual straight-line distance through the following formula: ； Among them, represents the actual straight-line distance between the current polishing trajectory point and the previous polishing trajectory point; represents the acceleration measured by the sensor module at the previous polishing trajectory point, represents the velocity measured by the sensor module at the previous polishing trajectory point, represents the measurement time of the sensor module; and then the distance error is obtained through the following formula: ； Among them, represents the distance error.

22. The magnetorheological polishing method for actuator adjustment according to claim 21, wherein: In step C4, when the polishing wheel is at the th polishing trajectory point, compare the current distance error , the distance error threshold and the regulation maximum value : When , the actuator group is not regulated; When , the actuator group is regulated: If the output displacement of the actuator group is the current distance error and the current polishing gap is where represents the polishing gap when the polishing wheel is at the th polishing trajectory point; If the output displacement of the actuator group is the maximum regulation value and the current polishing gap .

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